Electronic-grade hydrogen chloride tail gas recovery device

Abstract

The utility model relates to an electronic grade hydrogen chloride tail gas recovery device which is characterized in that a recovery tower, an absorption liquid recovery pool and a circulating pump are sequentially connected to form a loop, a spiral baffle is arranged in the middle of the recovery tower, a gas distributor is arranged at the bottom of the recovery tower, a gas inlet pipe is arranged on one side of the recovery tower, and a gas filter is arranged at the front end of the gas inlet pipe; the rear end of the gas inlet pipe extends into the bottom of the recovery tower and is divided into two gas guide pipes communicated with the gas distributor; a blow-down pipe is arranged at the top of the recovery tower. The recovery tower of the device does not need to be filled with filler, so that tedious work such as filler replacement is avoided; according to the device, the spiral baffle is adopted, bubbles rise along the baffle, the retention time of gas in absorption liquid is effectively prolonged, the tail gas recovery effect can be effectively improved, no gas accumulation dead angle exists in the device, and the absorption liquid can be smoothly circulated; according to the device, tail gas is absorbed by a liquid phase after aeration, gas and liquid are in full contact, and compared with traditional spraying recovery of hydrogen chloride tail gas, the tail gas escape phenomenon is effectively avoided.

Description

TECHNICAL FIELD

[0001] The utility model relates to the recovery unit of electronic grade hydrogen chloride tail gas. BACKGROUND

[0002] With the rapid development of the electronic industry, electronic grade hydrogen chloride (HCl), a kind of key chemical gas, is widely used in various production processes, such as semiconductor manufacturing, integrated circuit packaging, etc. However, the demand for electronic grade hydrogen chloride is increasing, which will generate a large amount of hydrogen chloride-containing tail gas. If these tail gases are directly discharged into the atmosphere without treatment, it will pose a serious threat to the environment and human health. Hydrogen chloride-containing gas combines with water vapor in the atmosphere to form acid rain, affecting the ecological balance and crop growth. In addition, direct discharge will also lead to resource waste. Therefore, it is crucial to recover hydrogen chloride-containing tail gas.

[0003] The current absorption device is mainly a spray tower. Patent CN219984338U proposes a hydrogen chloride tail gas recovery device, which includes a mixing box, a spray box and a filler box. The hydrogen chloride in the tail gas is recovered by the spray means through the filler layer, and a gas guide plate is arranged in the spray box to form an "S" type gas channel in the spray box, which is beneficial to further absorbing hydrogen chloride in the tail gas. However, the device is inclined downward, the gas guide plate is easy to cause gas accumulation, which increases the local pressure of the tower, is not conducive to gas venting, the filler layer cleaning and replacement work is tedious, and the spray means still allows a small amount of hydrogen chloride-containing gas to escape, and the treatment effect needs to be improved. SUMMARY

[0004] In view of the deficiencies of the existing hydrogen chloride tail gas recovery device, the purpose of the utility model is to provide a tail gas recovery device with sufficient gas-liquid contact and longer residence time, which avoids replacing the filler, to solve the problems of insufficient hydrogen chloride tail gas recovery of the existing recovery tower, tedious replacement of the filler, etc.

[0005] To achieve the above-mentioned purpose, the utility model provides the following technical scheme: a kind of electronic grade hydrogen chloride tail gas recovery device, recovery tower, absorption liquid recovery pool, circulating pump are connected into loop in proper order, the middle part of recovery tower is provided with spiral baffle, the bottom of recovery tower is equipped with gas distributor, one side of recovery tower is provided with inlet pipe, the front end of inlet pipe is provided with gas filter, the rear end of inlet pipe is deeply into the bottom of recovery tower and divides out two gas guide pipes to connect gas distributor, the top of recovery tower is provided with vent pipe.

[0006] Further, the bottom end of the inlet pipe branches out several gas guide pipes that are symmetrically distributed around the inlet pipe and evenly distributed, and are vertically connected to the inside of the gas distributor. A one-way valve is installed inside the gas guide pipe, and the interface is tightly connected, such as welding.

[0007] Further, the bottom of the recovery tower is communicated with the absorption liquid recovery tank through a regulating valve; and the outlet pipeline of the circulating pump is connected to the upper part of the recovery tower and is provided with a water return nozzle.

[0008] As a preferred scheme of the present application, the helical baffle is tightly connected with the inner wall of the recovery tower and the outer wall of the air inlet pipe, such as welding.

[0009] As a preferred scheme of the present application, the gas distributor comprises a buffer chamber and a gas distribution disc, the gas distribution disc is inclined downward to the center, and the surface is wrapped with rubber corrosion-resistant material; the buffer chamber is annular, and plays a buffering role in the aeration process to avoid liquid backflow to form a liquid seal, etc., the buffer chamber is tightly connected with the recovery tower (such as welding) on the outside, and the inner side passage is an absorption liquid backflow passage.

[0010] As a preferred scheme of the present application, a plurality of aeration heads are uniformly distributed on the gas distribution disc, and a plurality of aeration holes are distributed on the surface of the aeration head, when no gas is introduced, the rubber material on the surface of the hole is automatically closed by hydraulic pressure to prevent the recovery liquid from backflowing into the buffer chamber.

[0011] As a preferred scheme of the present application, a liquid discharge pipe is arranged at the bottom of the absorption liquid recovery tank, a liquid discharge valve is arranged on the liquid discharge pipe, a three-way branch analysis pipe is arranged at the front end of the liquid discharge valve, and an analysis valve is arranged on the analysis pipe; when the hydrogen chloride concentration in the recovery liquid reaches the upper limit standard, the liquid discharge valve is opened to discharge the recovery liquid, and at the same time, the circulating pump inlet front liquid supplement valve is opened to supplement water into the recovery tower, and the process does not need to stop.

[0012] As a preferred scheme of the present application, a liquid supplement pipe is arranged at the front end of the circulating pump inlet, and a liquid supplement valve is arranged on the liquid supplement pipe.

[0013] As a preferred scheme of the present application, a heat exchanger is arranged on the outlet pipeline of the circulating pump to cool the recovery liquid.

[0014] As a preferred scheme of the present application, the recovery tower is provided with a remote transmission type liquid level meter for monitoring the liquid level of the absorption liquid in the recovery tower, and the liquid level is used as a reference to control the opening degree of the regulating valve and the power of the circulating pump; when the liquid level decreases, the opening degree of the regulating valve is reduced, and the output power of the circulating pump is increased; on the contrary, when the liquid level rises, the opening degree of the regulating valve is increased, and the output power of the circulating pump is reduced, so as to ensure that the liquid level is dynamically stable and does not exceed the uppermost edge of the helical baffle.

[0015] Compared with the prior art, the electronic-grade hydrogen chloride tail gas recovery device has the following advantages:

[0016] 1. The device adopts a liquid phase absorption method to absorb the hydrogen chloride-containing tail gas, and the recovery tower does not need to be filled with a filler, thereby avoiding complicated work such as replacing the filler;

[0017] 2. The device adopts a spiral baffle, so that the bubbles rise along the baffle, effectively increasing the residence time of the gas in the absorption liquid, which can effectively improve the tail gas recovery effect, and there is no gas accumulation dead angle in the equipment, and the absorption liquid can smoothly circulate;

[0018] 3. The device adopts liquid phase absorption of tail gas after aeration, and the gas and liquid are in full contact, compared with the traditional spray recovery of hydrogen chloride tail gas, which effectively avoids the tail gas escape phenomenon. BRIEF DESCRIPTION OF DRAWINGS

[0019] Fig. 1 is the structural schematic diagram of the electronic-grade hydrogen chloride tail gas recovery device.

[0020] Fig. 2 is the structural schematic diagram of the gas distributor.

[0021] Fig. 3 is the structural schematic diagram of the aeration head.

[0022] Explanation of reference numerals in the drawing: 1. gas inlet pipe; 2. gas filter; 3. spiral baffle; 4. gas distributor; 41. gas guide pipe; 42. aeration head; 43. gas distribution disc; 44. aeration hole; 45. buffer chamber; 5. recovery tower; 6. absorption liquid recovery tank; 7. regulating valve; 8. liquid discharge pipe; 9. liquid discharge valve; 10. analysis pipe; 11. analysis valve; 12. liquid supplement valve; 13. liquid supplement pipe; 14. circulating pump; 15. liquid outlet pipe; 16. backwater pipe; 17. heat exchanger; 18. backwater spray head; 19. vent pipe; 20. remote transmission type liquid level meter. DETAILED DESCRIPTION

[0023] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application.

[0024] In the process of describing the present application, it should be noted that the terms "front", "back", "up", "down", "left", "right" and "center" and other descriptions of the position or mutual position relationship are all based on the position relationship shown in the drawings, and are only for the convenience of describing the present application, and are not specific to the described device or element must be a specific orientation and operation, therefore, it cannot be understood as a limitation on the present application; in addition, unless a specific limitation or limitation is described, the terms "connection", "setting", "connection" and the like should be understood broadly, for example, it can be detachable connection, or fixed connection, it can be mechanical connection, or electrical connection; it can be directly connected, or indirectly connected, or the interaction between the two devices. For ordinary skilled in the art, the specific meaning of the above terms in the present application can be understood in combination with the specific circumstances.

[0025] Embodiment 1

[0026] As Figs. 1-3 shown, an electronic grade hydrogen chloride tail gas recovery device, recovery tower 5, absorption liquid recovery pool 6, circulating pump 14 are connected in turn into a loop, the middle of the recovery tower is provided with a spiral baffle 3, the bottom of the recovery tower is provided with a gas distributor 4, the side of the recovery tower is provided with an air inlet pipe 1, the front end of the air inlet pipe is provided with a gas filter 2, the rear end of the air inlet pipe is deep into the bottom of the recovery tower and is divided into two gas guide pipes 41 connected with the gas distributor 4, the top of the tower is provided with a vent pipe 19, which is rainproof, the side of the recovery tower is provided with a remote liquid level meter 20;

[0027] Further, the bottom end of the air inlet pipe branches out several gas guide pipes which are symmetrical to the air inlet pipe and are evenly distributed, and are vertically connected to the inside of the gas distributor, a one-way valve is installed inside the gas guide pipe, and the interface is connected by welding.

[0028] The lower part of the recovery tower is communicated with the absorption liquid recovery pool 6 through the regulating valve 7, the absorption liquid recovery pool 6 is provided with a liquid outlet pipe 15, the inlet of the circulating pump 14 is connected with the liquid outlet pipe 15, and the outlet of the circulating pump 14 is communicated with the water return nozzle 18 at the upper part of the recovery tower through the water return pipe 16 to the inside of the recovery tower;

[0029] The spiral baffle 3 in the middle of the recovery tower 5 is tightly welded with the inner wall of the tower and the outer wall of the air inlet pipe on both sides, so as to avoid the rising of bubbles from the gap;

[0030] The gas distributor 4 includes a buffer chamber 45 and a gas distribution disc 43, the gas distribution disc 43 is inclined downward to the center, and the surface is wrapped with rubber corrosion-resistant material, which is beneficial to the absorption liquid to gather to the center along the distribution disc and flow to the recovery pool, the buffer chamber 45 is annular, and plays a buffering role in the aeration process, the outside of the buffer chamber 45 is tightly welded with the recovery tower 5, and the inside passage is an absorption liquid backflow passage;

[0031] Further, a plurality of aeration heads 42 are evenly distributed on the gas distribution disc 43, a plurality of aeration holes 44 are distributed on the surface of the aeration head 42, when no gas is introduced, the rubber material on the surface of the hole is automatically closed under the hydraulic pressure, preventing the recovery liquid from flowing back into the buffer chamber 45;

[0032] Further, the bottom of the absorption liquid recovery pool 6 is provided with a liquid discharge pipe 8, the liquid discharge pipe 8 is controlled to discharge liquid by a liquid discharge valve 9, the front end of the liquid discharge valve 9 is provided with a three-way branch analysis pipe 10, the analysis pipe 10 is controlled to analyze and sample by an analysis valve 11;

[0033] Further, the front end of the inlet of the circulating pump 14 is provided with a liquid supplement pipe 13, and the liquid supplement is controlled by a liquid supplement valve 12.

[0034] Furthermore, the return pipe 16 is provided with a heat exchanger 17 to cool the recovered liquid and promote the absorption of hydrogen chloride tail gas by the spray liquid.

[0035] The working principle of the electronic grade hydrogen chloride tail gas recovery device is described in detail below.

[0036] like Figs. 1-3 As shown, when the recovery tower is ready to be put into use, open the liquid replenishing valve 12 and the circulation pump 14 to replenish the recovery liquid into the recovery tower 5 until the remote liquid level gauge 20 shows that the liquid level is slightly higher than 80%. Then stop replenishing the liquid and adjust the opening of the regulating valve 7 so that the liquid amount in the absorption liquid recovery tank 6 reaches the normal working range of the circulation pump. If the recovery tower liquid level is less than 80% after adjustment, the recovery liquid can be appropriately added. After the circulation pump is working normally and the recovery tower liquid level is stable, the tail gas absorption operation can be carried out.

[0037] The working principle of this utility model is as follows: the tail gas containing hydrogen chloride enters the recovery tower 5 after being filtered through the gas filter 2 from the air inlet pipe 1, the tail gas enters the bottom of the recovery tower 5 along the air inlet pipe, enters the gas distributor 4 through the air guide pipe 41, and is temporarily stored in the buffer chamber 45. The tail gas in the buffer chamber 45 gathers at the aeration head on the surface of the gas distribution plate 43, and forms small bubbles through the aeration holes 44 and is exposed to the absorption liquid. The hydrogen chloride in the tail gas dissolves in the absorption liquid, and the insoluble gas rises with the spiral baffle 3, while the absorption liquid flows downward with the spiral baffle 3. During the process, the residual hydrogen chloride in the tail gas can still be absorbed. After the tail gas rises to the end of the upper end of the spiral baffle 3, it is discharged from the rainproof vent pipe 19. During operation, the heat exchanger 17 ensures that the recovery liquid is low in temperature and stable.

[0038] After the recovery tower has been in operation for a period of time, the analysis valve 11 is opened and the recovered liquid is sampled from the analysis tube 10 for analysis. If the hydrogen chloride concentration in the recovered liquid reaches the upper limit, the drain valve 9 can be opened to discharge the recovered liquid in the absorption liquid recovery tank 6 from the drain pipe 8. At the same time, the refill valve 12 must be opened to replenish the absorption liquid to stabilize the liquid level in the recovery tower 5. After replenishing the absorption liquid for a period of time, if the hydrogen chloride concentration in the absorption liquid in the absorption liquid recovery tank 6 is significantly reduced, the refilling and draining can be stopped, and the drain valve 9 and the refill valve 12 can be closed. There is no need to stop the machine during the entire process.

[0039] The above description, combined with the accompanying drawings, provides a detailed description of the embodiments of the present invention. However, the present invention is not limited to the embodiments described above, and the present invention is not limited by the above embodiments. For those skilled in the art, it is still possible to modify or replace the technical solutions described in the above embodiments with equivalents. Without departing from the spirit and principles of the present invention, any changes, replacements, modifications, etc. made must fall within the scope of protection of the present invention. The scope of protection claimed in this utility model is defined by the attached claims and their equivalents.

Claims

1. An electronic grade hydrogen chloride tail gas recovery device, characterized by: The recovery tower, absorption liquid recovery tank and circulation pump are connected in sequence to form a loop. A spiral baffle is provided in the middle of the recovery tower, a gas distributor is provided at the bottom of the recovery tower, an air inlet pipe is provided on one side of the recovery tower, a gas filter is provided at the front end of the air inlet pipe, the rear end of the air inlet pipe goes deep into the bottom of the recovery tower and is divided into two air guide pipes connected to the gas distributor, and a vent pipe is provided at the top of the recovery tower.

2. The electronic grade hydrogen chloride tail gas recovery device according to claim 1, characterized in that: The bottom of the air inlet pipe branches out into several air guide pipes that are symmetrically distributed with the air inlet pipe as the point and are vertically connected to the inside of the gas distributor. A one-way valve is installed inside the air guide pipe, and the interface is tightly connected.

3. The electronic grade hydrogen chloride tail gas recovery device according to claim 1, characterized in that: The bottom of the recovery tower is connected to the absorption liquid recovery tank through a regulating valve; the outlet pipe of the circulation pump enters the upper part of the recovery tower and is connected to a return water nozzle.

4. The electronic grade hydrogen chloride tail gas recovery device according to claim 1, characterized in that: Both sides of the spiral baffle are tightly connected to the inner wall of the recovery tower and the outer wall of the air inlet pipe respectively.

5. The electronic grade hydrogen chloride tail gas recovery device according to claim 1, characterized in that: The gas distributor includes a buffer chamber and a gas distribution plate. The gas distribution plate is inclined downward toward the center and the surface is wrapped with rubber anti-corrosion material. The buffer chamber is annular, the outer side of the buffer chamber is tightly connected to the recovery tower, and the inner channel is an absorption liquid reflux channel.

6. The electronic grade hydrogen chloride tail gas recovery device according to claim 5, characterized in that: A plurality of aeration heads are evenly distributed on the gas distribution plate, and a plurality of aeration holes are distributed on the surface of the aeration heads.

7. The electronic grade hydrogen chloride tail gas recovery device according to claim 1, characterized in that: A drain pipe is provided at the bottom of the absorption liquid recovery tank, a drain valve is provided on the drain pipe, a tee is provided at the front end of the drain valve to branch out an analysis pipe, and an analysis valve is provided on the analysis pipe.

8. The electronic grade hydrogen chloride tail gas recovery device according to claim 1, characterized in that: A fluid replenishment tube is provided at the front end of the circulation pump inlet, and a fluid replenishment valve is provided on the fluid replenishment tube.

9. The electronic grade hydrogen chloride tail gas recovery device according to claim 1, characterized in that: A heat exchanger is provided on the outlet pipeline of the circulation pump.

10. The electronic grade hydrogen chloride tail gas recovery device according to claim 1, characterized in that: The recovery tower is equipped with a remote liquid level gauge.

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